A Pittsburgh police officer was sued Tuesday over his encounter with a teacher who criticized his driving -- an incident that is being labeled a "racially motivated false arrest" by the American Civil Liberties Union of Pennsylvania.

Dennis Henderson lawsuit

The front page of the lawsuit that was filed on behalf of Dennis Henderson.

Some Pittsburghers spent part of their July 4th holiday rallying outside the city's Zone 5 police station, demanding that charges be dropped against a teacher and that the officer who arrested him be put on leave.

Dennis Henderson, who teaches at Manchester Academic Charter School, was jailed for about 12 hours on charges of obstructing traffic, becoming disorderly and resisting arrest after his June 26 brush with Officer Jonathan Gromek in Homewood.

All charges against Henderson were withdrawn by the district attorney, and Gromek was taken off patrol duty while the city's Office of Municipal Investigations reviewed the incident.

Henderson, 38, said he had just left a community meeting that addressed police relations and was giving contact information to a reporter on Kelly Street when Gromek drove by so quickly and so close that they called out, which led to the officer turning around and coming back.

Pittsburgh Police Bureau spokeswoman Diane Richard confirmed that the OMI sustained the allegations against Gromek, who is assigned to the warrant office as he awaits police internal action on his case. Gromek could not immediately be reached for comment.